https://support.apple.com/en-au/guide/ipad/ipad9a2465f9/ipados

Dictation

To enable Dictation on an iPad:

  1. Click Settings > General > Keyboard.
  2. Turn on Enable Dictation.

To use Dictation on the iPad:

  1. Click on the microphone key on the keyboard.
  2. Click on the keyboard key to stop dictation.

NOTE: This will also work on your iPhone and iPod.

Speak screen